1. Field of the Invention
This invention relates to analysis of audio signals using digital signal processing (DSP) in general, and, in particular, to the application of such analysis to automatically advance pages of a musical score, presentation, or text document, and/or to electronically compare an actual musical or spoken performance to the written script or score, thus providing feedback on performance errors to the performer, or the like.
2. Description of the Related Art
Musicians, actors, speakers, and others performing or presenting musical or other material typically use a musical score or written script to assist them in their performance. Often this score or script is in the form of multiple printed pages, necessitating page turns (sequencing from one page to the next) as the work progresses. These page turns can interrupt the flow of the music or presentation, especially during instrumental musical performance when the performer needs both hands to play an instrument. A speech or business presentation is also more effective without the interruptions of page turns. The Teleprompter™, a device which scrolls or pages text on a display device in view of the speaker, has been used for years by speakers to reduce or eliminate these interruptions from page turns.
Devices which electronically display a musical score are also described in the known art, as are mechanisms for advancing pages of such a display. One known solution, as described in U.S. Pat. No. 5,760,323 issued Jun. 2, 1998, the entirety of which is incorporated herein by reference, automatically turns or updates pages of a musical score displayed on an electronic display, responsive to a manual page-turn command input or by analysis of the audio and comparison to music as written in the score. However, there exists a need for additional and improved mechanisms for determining when to automatically initiate a page turn.
Teaching of musical performance typically involves a performer and teacher. The teacher, knowing the score and therefore the expected result of the performance, listens to the performance and then critiques all or part of it. The parameters used to judge the quality of performance include (but are not limited to) adherence to the score (playing the notes as written), pitch of each note, loudness of each note and phrase, and duration of each note. Once the performer is able to perform to a reasonable level of accuracy, additional practice without a teacher continues to improve the performance. During this solo practice, the performer critiques his performance, remembering the parameters previously taught.
In a similar manner, an actor or speaker is taught or learns his script or other presentation, and through practice continues to improve that performance and its adherence to the script. During such practice, it is often helpful to hear the lines spoken by others in the performance, to learn cues and understand the overall flow of the performance. A mechanism providing such practice without the need for the entire cast would be desirable.
Electronic comparison of a performance to its score or script would be desirable, providing feedback to the performer as to those areas requiring improvement in one or more of the measured parameters. Such a device would allow more rapid improvement and lessen the need for a teacher.